On the maximal flow problem with real arc capacities. - Jacob Ponstein (Math. Program., 1972)

On a general saddle-point condition in normed spaces. - Jacob Ponstein; Willem K. Klein Haneveld (Math. Program., 1975)

Comments on the general duality survey by J. Tind and L.A. Wolsey. - Jacob Ponstein (Math. Program., 1983)